Associations between smoke exposure and osteoporosis or osteopenia in a US NHANES population of elderly individuals

High prevalence of low bone mineral density in middle-aged adults in Shanghai: a cross-sectional study

PURPOSE

To assess bone mineral density (BMD) in middle-aged individuals in Shanghai, in order to improve awareness of osteopenia and osteoporosis screening.

METHODS

The clinical data of 1107 permanent residents of Shanghai aged 40-60 years were collected using a random cluster sampling method. Osteoporosis questionnaire survey and BMD test were conducted. Mann-Whitney U and Chi-square test were used to compare sex, age and body mass index at different stages of bone mass, and Pearson test was used to conduct correlation analysis. Logistic regression was used to analyze the influencing factors.

RESULTS

The detection rates of osteopenia and osteoporosis were 59% and 12.5% respectively, and bone mineral density was correlated with sex, age, and body mass index (P < 0.05).

CONCLUSION

The incidence of low bone mass is high in the assessed population, screening for low bone mass should be actively carried out to improve public awareness. It is also good for public health management.

REGISTERED CLINICAL TRIAL

The trial was approved by Chinese Clinical Trial Registry on February 11, 2021(ChiCTR2100043369).

Relationship between hypothyroidism and chronic kidney disease: Results from the National Health and Nutrition Examination Survey 2007 to 2012 and Mendelian randomization study

Chronic kidney disease (CKD) and hypothyroidism are prevalent chronic conditions with a generally believed correlation between them. However, large-scale population studies and investigations into causation are lacking. This study analyzed CKD and thyroid function data from the National Health and Nutrition Examination Survey database spanning 2007 to 2012 using multiple regression analyses to examine the correlation between CKD and hypothyroidism. Bidirectional Mendelian randomization analysis was employed to investigate the causal association between the two conditions. As CKD stages deteriorated, there was a significant decrease in total triiodothyronine (TT3) and free triiodothyronine (P < .05). However, no significant decrease was observed in total thyroxine and free thyroxine. Notably, there was a significant increase in thyroid-stimulating hormone levels (P < .05). However, no significant changes were observed in thyroglobulin, thyroglobulin antibody, and thyroid peroxidase antibody levels. A causal relationship between CKD and reduced thyroid function was observed (odds ratio [OR] = 1.0041, 95% confidence interval [CI]: 1.0007-1.0075, P = .0186). Conversely, reverse causality was not statistically significant (OR = 2.540, 95%CI: 0.8680-4.8603, P = .1014). As CKD progressed, the risk of hypothyroidism increased. A causal correlation was observed between CKD and reduced thyroid function. Chronic kidney disease (CKD) and hypothyroidism are prevalent chronic conditions with a generally believed correlation between them. There is no large-scale population studies and the causation relationship between CKD and hypothyroidism are lacking. The finding of the causal relationship between CKD and hypothyroidism may be beneficial to the prevention of the disease and the prognosis of the patients.

Yogurt consumption and risk of accelerated aging: A population-based study from the NHANES 2003-2006

Introduction

Yogurt consumption is beneficial to health, but its association with aging remains unclear. This study aims to explore the relationship between yogurt consumption and aging using data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES).

Methods

We used data from 4,056 participants to examine the relationship between yogurt consumption and aging. Yogurt consumers were defined as individuals who consumed yogurt at least once per year. Phenotypic age acceleration was used as a surrogate marker for aging. Nearest-neighbor propensity score matching (PSM) was applied to reduce bias, followed by weighted multivariate logistic regression analysis, subgroup analysis, and restricted cubic spline (RCS) to investigate the relationship between yogurt consumption and aging.

Results

Yogurt consumption was associated with a lower risk of accelerated aging compared to non-consumers (OR = 0.544, 95% CI: 0.354-0.836, p = 0.020). A U-shaped relationship was observed between the frequency of yogurt intake and the risk of accelerated aging. Additionally, yogurt consumption was related to a lower risk of overweight status.

Discussion

These findings suggest that yogurt consumption may reduce the risk of accelerated aging and may also be linked to a lower risk of overweight status. This could provide a promising avenue for exploring the beneficial effects of dietary factors on lifespan extension.

Volatile organic compounds (VOC) metabolites in urine are associated with increased systemic inflammation levels, and smokers are identified as a vulnerable population

BACKGROUND

Previous studies indicated that exposure to VOCs was linked to increased systemic inflammation levels. However, the dose-response relationships between urine VOCs metabolites and systemic inflammation have not been established, and the key metabolite of the toxic compounds has not been identified.

METHODS

We used data in 7007 US adults in the NHANES cycles (2011-2018) across 8 years. Urinary VOC metabolites were measured using ultra-performance liquid chromatography and electrospray tandem mass spectrometry (UPLC-ESI/MSMS). VOC metabolites were adjusted by urinary creatinine level before analysis. Systemic inflammation was assessed by systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI) indices. Generalized linear models, restricted cubic splines (RCS), and weighted quantile sum (WQS) regression were applied to evaluate the associations, exposure-response (E-R) curve and identify the key contributor compound, adjusting for gender, age, race, BMI, marital condition, education level, smoking level, alcohol consumption and physical activity. Smoking status was assessed as an effect modifier.

RESULTS

Significant and robust positive correlations were found between 8 VOC metabolites and both SII and SIRI. They were N-Acetyl-S-(2-carboxyethyl)-L-cysteine (CEMA), N-Acetyl-S-(2-cyanoethyl)-L-cysteine (CYMA), N-Acetyl-S-(3,4-dihydroxybutyl)-L-cysteine (DHBMA), N-Acetyl-S-(3-hydroxypropyl)-L-cysteine (3HPMA), mandelic acid (MA), N-Acetyl-S-(4-hydroxy-2-butenyl)-L-cysteine (MHBMA3), phenylglyoxylic acid (PGA), and N-Acetyl-S-(3-hydroxypropyl-1-methyl)-L-cysteine (HPMMA). The RCS curves showed J-shaped or exponential shaped E-R relationships for most VOC metabolites. WQS regression found that exposure to the mixture of VOC metabolites was related to increased systemic inflammation, and MA was the key VOC metabolite contributing most to systemic inflammation levels. Smokers exhibited higher levels of urinary VOCs and larger susceptibility to VOC-related increases in SII and SIRI compared to non-smokers.

CONCLUSION

This study demonstrated a strong link between urinary VOC metabolites and increased systemic inflammation, and smokers were more susceptible. Our findings highlighted the significance of reducing VOC exposure to mitigate the inflammation levels, particularly for smokers.

The mediating role of inflammation in the association between cotinine levels and remnant cholesterol: a cross-sectional study

BACKGROUND

Remnant Cholesterol (RC) has emerged as a significant risk factor for cardiovascular disease. However, the factors influencing RC levels remain incompletely understood. This research investigates smoking-a major modifiable risk factor-to elucidate its impact on RC levels and examine the mediating role of inflammation in this relationship.

METHODS

Using NHANES data from 1999 to 2018, this study analyzed the association between serum cotinine levels (a biomarker of smoking intensity) and RC in 8,829 participants aged 20 years and older. Through complex sampling design and adjustment for multiple covariables, we examined both linear and nonlinear relationships using linear regression models, restricted cubic splines (RCS), and subgroup analyses. Additionally, mediation analyses evaluated the role of inflammatory markers-neutrophils (NEU), monocytes (MON), lymphocytes (LYM), and platelets (PLT)-in this association.

RESULTS

The high cotinine exposure group demonstrated significantly elevated RC levels (β = 2.256, 95% CI: 1.401-3.112, p < 0.001) compared to the no/minimal exposure group. This positive association was particularly pronounced in females (p for interaction < 0.05). Restricted cubic spline analysis demonstrated a nonlinear, N-shaped relationship (p for nonlinearity < 0.05), with RC levels reaching their peak at cotinine concentrations of approximately 172 ng/mL. In the mediation analysis, inflammatory markers showed significant mediating effects: NEU (28%), LYM (14.1%), PLT (9.5%), and MON (6.9%) of the total effect.

CONCLUSION

A significant positive association exists between cotinine and RC levels, moderated by sex. Inflammatory markers, particularly NEU, partially mediate this association.

Does higher serum 25-hydroxyvitamin D levels will harm bone mineral density?: a cross-sectional study

OBJECTIVE

Vitamin D plays a critical role in the prevention and management of osteoporosis. However, there is an ongoing debate regarding the most effective vitamin D supplementation strategies for maintaining optimal bone mineral density (BMD) levels in adults. This study sought to establish the correlation between serum 25-hydroxyvitamin D [25(OH)D] levels and total BMD in a substantial population sample.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) for the 2011-2018 cycles, encompassing 11,375 adult participants, were analyzed. The primary variables of interest were serum 25(OH)D levels and BMD. A multivariable logistic regression model was utilized to account for relevant variables associated with these correlations.

RESULTS

A U-shaped relationship between serum 25(OH)D levels and BMD was observed. In males, a significant positive association was identified for 25(OH)D levels below 84.8 nmol/L (p < 0.0001), while levels above this threshold showed no significant correlation (p = 0.3377). In females, those with 25(OH)D levels below 31.4 nmol/L exhibited a significant positive association with BMD (p = 0.0010), but this association weakened and became marginally significant above this threshold (p = 0.0650).

CONCLUSIONS

For adult males, the optimal serum 25(OH)D level is 84.8 nmol/L, beyond which higher levels do not lead to increased BMD. A deficiency threshold for adult females should be above 31.4 nmol/L, as lower 25(OH)D levels are not conducive to BMD. These findings underscore the importance of maintaining appropriate vitamin D levels for bone health in both genders.

Clinical and subclinical arteriosclerotic disease in octagenarians with hip fracture. A case-control study

BACKGROUND AND OBJECTIVES

Evaluate clinical and subclinical arteriosclerotic disease in older patients with hip fracture compared with patients without fracture in order to increase knowledge about the relation between both diseases in older individuals.

PATIENTS AND METHODS

Age- and sex-matched case-control study of octogenarians with and without recent hip fracture. Vascular risk factors, subclinical vascular diseases (assessed by carotid plaques, carotid intima media thickness and arterial stiffness) as well as cardiovascular diseases were analyzed. Univariate and multivariate logistic models were used to estimate odds ratios (OR) with their 95% confidence intervals (CI) to assess the association of the arteriosclerosis and hip fracture.

RESULTS

We analyzed 95 patients per group with a median age of 82 [79-87] years of whom 77.9% were female. Patients in both groups have elevated rates of vascular disease (25%) without differences between them. Patients with hip fracture had higher subclinical arteriosclerotic alterations with higher percentage of carotid plaques (OR 3.25 [1.06-9.97]) compared with the control group.

CONCLUSIONS

Older patients with hip fracture had significantly higher presence of subclinical alterations but not increase on rate of cardiovascular arteriosclerotic disease compared with those without hip fracture.

Serum vitamin C levels and risk of osteoporosis: results from a cross-sectional study and Mendelian randomization analysis

BACKGROUND

The role of vitamin C as an antioxidant in guarding against osteoporosis in adults is still debated. This research employs both a cross-sectional study and a two-sample bidirectional Mendelian randomization (MR) analysis to explore how serum vitamin C levels correlate with the incidence of osteoporosis among adults.

METHODS

In this study, we utilized data from the National Health and Nutrition Examination Survey (NHANES) database for the years 2003-2006, and 2017-2018 to conduct both a cross-sectional analysis and MR to investigate the relationship between serum vitamin C levels and the risk of osteoporosis in adults. We adjusted our analyses for essential demographic and lifestyle variables, and applied logistic regression techniques. Genetic determinants of vitamin C levels were analyzed through MR, using methods like inverse-variance weighted (IVW) and MR-Egger to assess causality. Statistical computations were carried out in R, incorporating visual tools such as restricted cubic spline curves (RCS) and forest plots to clarify the dose-response dynamics and variations across different subgroups. This study was approved by the NCHS Ethics Review Board, and informed consent was obtained from all participants.

RESULTS

In our investigation, we analyzed data from 3,940 participants, among whom 291 were diagnosed with osteoporosis. The logistic regression analysis of serum vitamin C quartiles did not indicate a significant trend. The most adjusted model showed a slight, albeit inconsistent, protective effect in the highest quartile (OR = 0.68, 95% CI: 0.47-0.99, P = 0.22). Mendelian randomization, employing methods such as IVW, reinforced the absence of a significant causal relationship between serum vitamin C levels and osteoporosis risk (IVW OR = 1.000, 95% CI: 0.999-1.001, P = 0.601).Subgroup analyses, visualized through forest plots and restricted cubic spline (RCS) curves, supported the primary findings, showing no significant effects or interactions between vitamin C levels and osteoporosis risk across different demographic and lifestyle subgroups. The RCS analysis particularly highlighted a lack of significant non-linear relationships between serum vitamin C concentration and the odds of osteoporosis (P for nonlinear = 0.840).

CONCLUSIONS

The cross-sectional study revealed that higher serum vitamin C levels do not consistently correlate with a reduced risk of osteoporosis. Meanwhile, the Mendelian randomization analysis confirmed that there is no genetic evidence to suggest a causal relationship between vitamin C levels and osteoporosis risk. Recent research highlights the polygenic nature of osteoporosis, with genetic predispositions playing a significant role in disease risk. The relationship between serum vitamin C and osteoporosis requires further research. This suggests the need for further investigation into the connection between vitamin C and bone health.

Interaction Between Tobacco Smoke Exposure and Zinc Intake and Its Effect on Periodontitis: Evidence From NHANES

AIM

Tobacco smoke exposure, zinc intake, and periodontitis are closely related. This study intended to assess the relationship between tobacco smoke exposure and zinc intake and its effect on periodontitis.

MATERIALS AND METHODS

This cross-sectional study included 9364 participants from the National Health and Nutrition Examination Survey (NHANES) of USA. A weighted multivariate logistic regression model was used to investigate the independent relationship and interaction effect among tobacco smoke exposure, zinc intake, and periodontitis. Odds ratio (OR) with 95% confidence interval (CI) was calculated. The additive interaction was evaluated using relative excess risk due to interaction (RERI), attributable proportion of interaction (AP), and synergy index (SI).

RESULTS

In all, 56.57% participants had periodontitis. Compared with participants without tobacco smoke exposure, those with tobacco smoke exposure had increased odds of having periodontitis (OR, 1.96; 95% CI, 1.67-2.31). Similarly, patients with adequate zinc intake were found to have decreased odds of having periodontitis than those with inadequate zinc intake (OR, 0.86; 95% CI, 0.76-0.98). Importantly, there was antagonistic interaction effect between zinc intake and tobacco smoke exposure on periodontitis (RERI: OR,  -0.432; 95% CI, -0.829 to -0.034; AP: OR, -0.242; 95% CI, -0.470 to -0.014; SI:  OR, 0.645; 95% CI, 0.446 to 0.932).

CONCLUSIONS

Tobacco smoke exposure and zinc intake were independently correlated with periodontitis risk. Decreasing tobacco smoke exposure and optimizing dietary zinc intake appear to be important measures that could be taken to control periodontitis.

Association between sleep duration and sleep quality with pre-sarcopenia in the 20-59-year-old population: evidence from the National Health and Nutrition Examination Surveys 2005-2014

BACKGROUND

Sarcopenia is a musculoskeletal disease characterized by a significant reduction in muscle mass, strength, and performance. As it mostly affects older adults, it is often recognized as a disease of old age. However, sleep is also closely related to its development. Hence, it becomes critical to explore the relationship between sleep and sarcopenia in populations under 60 years of age to develop strategies for preventing sarcopenia. We here aim to explore the specific association between sleep duration and sleep quality with pre-sarcopenia in the non-elderly population using large population samples.

METHODS

This study involved 7,187 participants aged 20-59 years from the National Health and Nutrition Examination Survey (NHANES) conducted between 2005 and 2014. Pre-sarcopenia is defined based on the appendicular skeletal muscle mass (ASM) adjusted for body mass index (BMI). Self-reported sleep duration was categorized into three groups: <6 h (short sleep), 6-8 h (normal sleep), and > 8 h (long sleep). Sleep quality was assessed based on the Sleep Disorder and Trouble Sleeping Questionnaire. Univariate analysis and multivariate logistic regression were used to examine the relationship between sleep duration and sleep quality with pre-sarcopenia.

RESULTS

Sleep quality was significantly linked with the risk of pre-sarcopenia (OR 1.72, 95% CI 1.36-2.18, P < 0.01). Longer or shorter sleep duration did not affect the risk of pre-sarcopenia, in contrast to normal sleep duration. Subgroup analysis demonstrated a more pronounced association in individuals who are > 40 years old (P < 0.01), non-Hispanic (P ≤ 0.01), overweight (P < 0.01), have a higher income (P < 0.01), and are more educated (P ≤ 0.01). Moreover, this association was noted in populations with or without smoking (P < 0.01) and alcohol consumption (P < 0.01), hypertension (P < 0.01) and diabetes (P ≤ 0.02).

CONCLUSION

Sleep quality is associated with an increased risk of pre-sarcopenia, while sleep duration is not in the population aged 20-59 years. Further prospective cohort studies with a large sample size are needed to determine causality and develop effective interventions for preventing sarcopenia in the population aged 20-59 years.

Serum cotinine levels and adolescents' sleep health outcomes from NHANES 2005 to 2018

The association between tobacco smoke exposure and sleep has been widely discussed, but the correlation between serum cotinine levels and sleep health outcomes in adolescents has not been well described. This study aimed to further evaluate the association between serum cotinine levels and sleep health outcomes in adolescents using data from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. This cross-sectional study included participants aged 16-19 years from the NHANES 2005-2018. A weighted multivariate logistic regression model was used for the primary analysis. A restricted cubic spline (RCS) model was employed to investigate the non-linear association between serum cotinine levels and trouble sleeping. Subgroup analyses based on population characteristics were also conducted. In total, 2630 participants were included, which are representative of the 11.5 million US adolescents. Higher serum cotinine levels (≥ 3 ng/ml) were significantly associated with trouble sleeping in the fully adjusted model (odds ratio [OR] 1.817). The RCS model revealed a non-linear relationship between serum cotinine levels and trouble sleeping. Subgroup analyses indicated that this relationship was consistent and stable across various population characteristics. Serum cotinine levels are associated with sleep health outcomes in adolescents, with high serum cotinine levels being linked to increased trouble sleeping and longer or shorter sleep duration.

Associations between life's essential 8 and femoral neck bone mineral density among adults: A national population-based study

Osteoporosis represents a significant public health issue, impacting both health outcomes and economic costs. This research investigates how cardiovascular health, as indicated by the LE8 score, correlates with bone mineral density (BMD). Data from the National Health and Nutrition Examination Survey (NHANES) spanning 2011 to 2018 were analyzed in this cross-sectional analysis, including 9018 subjects following the exclusion of individuals lacking BMD or LE8 data. The LE8 score, comprising factors such as diet, physical activity, smoking status, sleep quality, body mass index, lipid profiles, blood glucose, and blood pressure, was used to evaluate cardiovascular health. BMD was determined through dual-energy X-ray absorptiometry (DXA). Relationships between the LE8 scores and BMD at the femoral neck were assessed using linear regression and smooth curve fitting techniques. Enhanced LE8 scores were linked to improved BMD at the femoral neck. Notably, a 10-point increment in the LE8 score was associated with a rise in BMD by 0.04 g/cm² [β = 0.04, 95% CI: 0.03-0.05]. The data indicate a strong positive association between cardiovascular health, as measured by LE8, and BMD. These results support the development of holistic health strategies that promote cardiovascular health to potentially improve bone density.

Associations of oxidative balance score with lumbar spine osteopenia in 20-40 years adults: NHANES 2011-2018

PURPOSE

Current research suggests that oxidative stress may decrease bone mineral density (BMD) by disrupting bone metabolism balance. However, no study investigated the relationship between systemic oxidative stress status and adult BMD. This study aims to investigate whether oxidative balance score (OBS) is associated with BMD in adults under 40.

METHODS

3963 participants were selected from the National Health and Nutrition Survey (NHANES) from 2011 to 2018. OBS is scored based on 20 dietary and lifestyle factors. Weighted multiple logistic regression and restricted cubic splines were used to assess the correlation between OBS and osteopenia.

RESULTS

After adjusting for confounding factors, the weighted logistic regression results showed that compared with the first tertile of OBS, the highest tertile had a 38% (OR: 0.62, 95% CI: 0.47-0.82) lower risk of osteopenia. The restrictive cubic spline curve indicates a significant nonlinear correlation between OBS and the risk of osteopenia.

CONCLUSION

The research findings emphasize the relationship between OBS and the risk of osteopenia in young adults. Adopting an antioxidant diet and lifestyle may help young adults to maintain bone mass.

Association between yogurt and dietary supplements containing probiotic consumption with sleep disturbance in US adults: Results from NHANES, 2009-2018

Purpose

Sleep disorders are common globally. Probiotics may improve human microbial diversity, offering potential benefits for sleep disturbances by enhancing sleep quality and reducing disorders. We aimed to use a population-based study to investigate the association between yogurt (a probiotic food) and probiotic consumption with sleep disturbances in US adults.

Methods

A total of 49,693 adults from the 2009-2018 National Health and Nutrition Examination Survey (NHANES) were included in the analyses. Sleep disorders and sleep duration were assessed according to the Sleep Disorders Questionnaire. The Dietary Questionnaire evaluated yogurt and dietary supplements containing probiotic consumption. After adjusting for confounding factors, weighted multivariable logistic regression and subgroup analyses were used to assess the association between yogurt and probiotic consumption and sleep status.

Results

Of the study cohort, 3535 (14.24 %) participants consumed yogurt and/or dietary supplements containing probiotics. The prevalence of sleep disorders was 16.22 %. Only 53.51 % of the participants achieved the recommended amount of sleep (7-9 h), with 6.10 % and 33.48 % having excessive and insufficient sleep duration, respectively. Weighted Logistic regression models indicated a significant association of probiotic intake with a decreased risk of sleep disturbances compared with those without yogurt or probiotic consumption after adjustments. (For sleep disorders: OR: 0.96, 95 % CI 0.94-0.98, P < 0.001; for sleep duration: OR: 0.98, 95 % CI 0.96-1.00, P = 0.081) Moreover, the effect size of the probiotic intake on sleep was especially significant in sex, race, and BMI subgroups.

Conclusion

The present study first indicated that yogurt and probiotic consumption were associated with a reduced risk of sleep disturbances in US adults, particularly among males, whites, and those with a normal BMI. Incorporating yogurt or probiotics into the diet could serve as a public health strategy for improving sleep disturbances, though further investigation into the underlying mechanisms is needed.

Association between dietary copper, iron, zinc, selenium intake and osteopenia or osteoporosis in elderly hypertensive patients: a retrospective cohort study

Aim

The study aimed to investigate the link between dietary copper, iron, zinc, selenium intake with osteopenia and osteoporosis in elderly hypertensive patients.

Methods

The data of hypertensive patients were extracted from the National Health and Nutrition Examination Survey 2005-2010, 2013-2014, and 2017-2018. Data of dietary iron, zinc, copper and selenium intakes were obtained according to 24-h diet recall interviews. Osteopenia and osteoporosis were determined based on the bone mineral density. Weighted liner regression and weighted logistic regression were employed to assess the association between iron, zinc, copper, and selenium intakes with osteopenia and osteoporosis. All results were presented as β, odds ratios (ORs), and 95% confidence intervals (CIs).

Results

In total, 5,286 elderly hypertensive patients were included. Among them, 2,961 (56.02%) patients have osteopenia, and 566 (10.71%) have osteoporosis. After adjusting all covariates, dietary copper intake ≥the recommended daily allowance was positively correlated with bone mineral density on total femur (β = 0.086, 95% CI: 0.021-0.152) and femoral neck (β = 0.097, 95% CI: 0.016-0.178). Dietary zinc intake ≥the recommended daily allowance was also positively correlated with bone mineral density on total femur (β = 0.092, 95% CI: 0.030-0.153) and femoral neck (β = 0.122, 95% CI: 0.050-0.193). Dietary copper (O = 0.581, 95% CI: 0.394-0.858) and zinc (OR = 0.595, 95% CI: 0.429-0.827) intake ≥the recommended daily allowance levels were related to increased odds of osteoporosis in elderly with hypertension.

Conclusion

Higher dietary copper and zinc intake was associated with lower odds of osteoporosis in the elderly hypertensive patients. Higher dietary intake included copper and zinc may be beneficial for the bone health in the elderly hypertensive patients.

Association between serum cotinine and muscle mass: results from NHANES 2011-2018

PURPOSE

Recently, the detrimental effect of cigarette smoking on muscle metabolism has attracted much attention, but the relationship between cigarette smoking and muscle mass is poorly understood. Thus, this study investigated the association between exposure to cigarette smoke, defined based on serum cotinine, and muscle mass in the US population.

METHODS

We utilized National Health and Nutrition Examination Survey (NHANES) data between 2011 and 2018 for analysis. Data on serum cotinine, muscle mass (quantified by appendicular skeletal muscle mass index, ASMI), and covariates were extracted and analyzed. Weighted multivariate linear regression analyses and smooth curve fittings were performed to investigate the association between serum cotinine and ASMI. Subgroup analyses were stratified by gender, race and smoking status. When nonlinearity was detected, the threshold effects were analyzed using a two-piecewise linear regression model.

RESULTS

In total, 8004 participants were included for analysis. The serum level of cotinine was negatively associated with ASMI in the fully adjusted model. Furthermore, comparing participants in the highest vs. the lowest tertile of serum cotinine, we found that ASMI decreased by 0.135 Kg/m2. In subgroup analysis stratified by gender and race, the association between serum cotinine and ASMI remained significant in all genders and races. In addition, the association remained significant among current and former smokers, but not among those who never smoked. Smooth curve fittings showed nonlinear relationships between serum cotinine and ASMI, with the inflection points identified at 356 ng/mL.

CONCLUSIONS

Our study revealed that serum cotinine was negatively related to muscle mass. This finding improves our understanding of the deleterious effects of cigarette smoking on muscle mass and highlights the importance of smoking cessation for muscle health.

Investigating the Effects and Mechanisms of Combined Vitamin D and K Supplementation in Postmenopausal Women: An Up-to-Date Comprehensive Review of Clinical Studies

Aging is a complex process and a significant risk factor for chronic diseases. Menopause, a component of aging in women, is associated with several important cardiometabolic conditions including metabolic syndrome, osteoporosis, and cardiovascular diseases. Menopausal women could benefit from preventative strategies that may decrease morbidity and mortality and improve their quality of life. Vitamins D and K are essential nutrients required for bone health, immune function, and reducing cardiovascular risks, yet their synergistic effect is less understood in aging women. This is the first comprehensive review to summarize the evidence found in randomized clinical trials of the beneficial effects of vitamin D and K co-treatment in postmenopausal women. In our literature search across key electronic databases such as Cochrane, PubMed, and Ovid, we identified 31 pertinent studies. Overall, significant findings indicate that the combined intake of vitamins D and K may positively affect cardiovascular and bone health in postmenopausal women, emphasizing the importance of maintaining a healthy diet rich in vegetables and fermented dairy products. Given the challenges in obtaining all necessary nutrients solely through the diet, vitamin D and K supplements are recommended for postmenopausal women to promote healthy aging and well-being.

Association between weight-adjusted waist index and bone mineral density in adolescents

The negative effects of obesity and excess body fat on bone mineral density (BMD) have been widely reported. As opposed to waist circumference (WC) or body mass index (BMI), weight-adjusted waist index (WWI) is a superior method for assessing obesity. WWI also indicates centripetal obesity independently of the weight of the individual. An investigation of WWI and adolescents' BMD was conducted in this study. The National Health and Nutrition Examination Survey (NHANES) 2011-2018 provided the data for this cross-sectional investigation. In this study, weighted multivariate logit models were employed to assess the correlation between teenage BMD and WWI. Additionally, we conducted interaction tests and subgroup analysis. Through multivariate linear regression, we discovered that WWI was negatively linked with lumbar, trunk, and total BMD but not pelvis BMD in this study, which included 6828 subjects. We found that each unit increase in WWI resulted in a lumbar BMD decline of 0.04 g/cm2 (95%CI -0.04, -0.04), a trunk BMD decrease of 0.03 g/cm2 (95%CI -0.03, -0.02), and a total BMD decrease of 0.02 g/cm2 (95%CI -0.02, -0.02). In conclusion, in US teenagers, there were negative connections discovered between WWI and lumbar, trunk, and total BMD, but not pelvis BMD.

Association between tobacco smoke exposure and serum parathyroid hormone levels among US adults (NHANES 2003-2006)

Tobacco smoke exposure has been demonstrated to impede bone remodeling and diminish bone density, yet research regarding its correlation with parathyroid hormone (PTH) remains limited. This study aims to investigate the relationship between tobacco smoke exposure and serum PTH levels in adults aged 20 years and older. This study included 7,641 participants from two cycles of the National Health and Nutrition Examination Survey (NHANES, United States, 2003- 2006). Reflect tobacco smoke exposure through serum cotinine levels, and use an adjusted weighted multivariate linear regression model to test the independent linear relationship between serum cotinine and PTH. Stratified analysis was conducted to validate the sensitivity of the conclusions. Smooth curve fitting and threshold effect analysis were performed to assess the non-linear relationship. After comprehensive adjustment using weighted multivariate regression analysis, a negative correlation was found between serum cotinine and PTH levels. The interaction p-values in subgroup analyses were all greater than 0.05. Moreover, smooth curve fitting indicated a non-linear relationship between serum cotinine and PTH, with a turning point observed. Our research indicates that tobacco smoke exposure is negatively correlated and independent of serum parathyroid hormone levels, indicating that long-term tobacco smoke exposure may lead to parathyroid dysfunction in adults.

Association between tobacco smoke exposure and depression: the NHANES 2005-2018 and Mendelian randomization study

OBJECTIVE

The relationship between tobacco smoke exposure (TSE) and depression is controversial. This study combined observational research and Mendelian randomization (MR) to explore the relationship of depression with both smoking status and cotinine levels.

METHOD

We collected relevant data from the National Health and Nutrition Examination Survey (NHANES) database from 2005 to 2018, and used weighted multifactorial logistic regression modelling to assess the correlation between TSE and depression, and assessed the causal relationship of depression with both smoking status and cotinine levels by MR.

RESULT

Current smokers had the highest risk of depression (OR 1.94; P < 0.01); there was a positive trend for correlation between daily smoking and depression (OR 1.66; P for trend < 0.01). Serum ketamine levels above 3.00 ng/ml had a higher risk of depression (OR 2.13; P < 0.001). MR results showed that current smoking (OR = 4.66; P < 0.001) and previous smoking (OR 2.09; P < 0.01) were risk factors for the onset of depression, and that there was no causal association between cotinine levels and depression.

CONCLUSION

Smoking is significantly associated with depression and plays a potential causal role in the development of depression. Cotinine was significantly associated with depression, however MR results showed no causal relationship between cotinine and depression.

The association of smoking on the increased risk of osteoporotic fracture: Results from a cross-sectional study and two-sample Mendelian randomization

INTRODUCTION

We conducted analyses of the association between smoking and osteoporosis and osteoporotic fractures using a secondary dataset analysis of the National Health and Nutrition Examination Survey (NHANES) database and the two-sample Mendelian randomization (MR) method.

METHODS

The associations between smoking and osteoporosis or osteoporotic fractures were analyzed using weighted logistic regression models for both univariate and multivariable analyses using pooled 1999-2018 NHANES data. The summary-level data of genome-wide association studies (GWAS) of smoking and osteoporosis were extracted from the IEU Open GWAS project. The inverse variance weighted method was used as the main method for the two-sample MR analysis.

RESULTS

We obtained the following main findings based on the NHANES data: smoking was associated with osteoporosis according to the analyses of 30856 participants (OR=1.21; 95% CI: 1.06-1.39, p=0.004); smoking was associated with hip osteoporotic fracture according to the analyses of 30928 participants (OR=1.47; 95% CI: 1.14-1.90, p=0.004); smoking was associated with wrist osteoporotic fracture according to the analyses of 30923 participants (OR=1.33; 95% CI: 1.18-1.49, p<0.001); and smoking was associated with spine osteoporotic fracture according to the analyses of 30910 participants (OR=1.43, 95% CI: 1.18-1.73, p<0.001). In addition, we confirmed the potential causal effect of smoking on the risk of osteoporotic fracture (OR=24.5; 95% CI: 1.11-539, p=0.043) by conducting two-sample MR analyses.

CONCLUSIONS

Smoking was associated with increased risks of both osteoporosis and osteoporotic fracture. Smoking showed a potential causal effect on the risk of osteoporotic fracture.

Characterization of cotinine degradation in a newly isolated Gram-negative strain Pseudomonas sp. JH-2

Cotinine, the primary metabolite of nicotine in the human body, is an emerging pollutant in aquatic environments. It causes environmental problems and is harmful to the health of humans and other mammals; however, the mechanisms of its biodegradation have been elucidated incompletely. In this study, a novel Gram-negative strain that could degrade and utilize cotinine as a sole carbon source was isolated from municipal wastewater samples, and its cotinine degradation characteristics and kinetics were determined. Pseudomonas sp. JH-2 was able to degrade 100 mg/L (0.56 mM) of cotinine with high efficiency within 5 days at 30 ℃, pH 7.0, and 1% NaCl. Two intermediates, 6-hydroxycotinine and 6-hydroxy-3-succinoylpyridine (HSP), were identified by high-performance liquid chromatography and liquid chromatograph mass spectrometer. The draft whole genome sequence of strain JH-2 was obtained and analyzed to determine genomic structure and function. No homologs of proteins predicted in Nocardioides sp. JQ2195 and reported in nicotine degradation Pyrrolidine pathway were found in strain JH-2, suggesting new enzymes that responsible for cotinine catabolism. These findings provide meaningful insights into the biodegradation of cotinine by Gram-negative bacteria.

Sexual dimorphism association of combined exposure to volatile organic compounds (VOC) with kidney damage

BACKGROUND

Epidemiological evidence emphasizes air pollutants' role in chronic kidney disease (CKD). Volatile organic compounds (VOCs) contribute to air pollution, yet research on VOCs and kidney damage, especially gender disparities, is limited.

METHODS

This study analyzed NHANES data to explore associations between urinary VOC metabolite mixtures (VOCMs) and key kidney-related parameters: estimated glomerular filtration rate (eGFR), albumin-to-creatinine ratio (ACR), chronic kidney disease (CKD), and albuminuria. Mediation analyses assessed the potential mediating roles of biological aging (BA) and serum albumin in VOCM mixtures' effects on kidney damage. Sensitivity analyses were also conducted.

RESULTS

The mixture analysis unveiled a noteworthy positive association between VOCM mixtures and the risk of developing CKD, coupled with a significant negative correlation with eGFR within the overall participant cohort. These findings remained consistent when examining the female subgroup. However, among male participants, no significant link emerged between VOCM mixtures and CKD or eGFR. Furthermore, in both the overall and female participant groups, there was an absence of a significant correlation between VOCM mixtures and either ACR or albuminuria. On the other hand, in male participants, while no significant correlation was detected with albuminuria, a significant positive correlation was observed with ACR. Pollutant analysis identified potential links between kidney damage and 1,3-butadiene, toluene, ethylbenzene, styrene, xylene, acrolein, crotonaldehyde and propylene oxide. Mediation analyses suggested that BA might partially mediate the relationship between VOCM mixtures and kidney damage.

CONCLUSION

The current findings highlight the widespread exposure to VOCs among the general U.S. adult population and indicate a potential correlation between exposure to VOC mixtures and compromised renal function parameters, with notable gender disparities. Females appear to exhibit greater sensitivity to impaired renal function resulting from VOCs exposure. Anti-aging treatments may offer some mitigation against kidney damage due to VOCs exposure.

Development and internal validation of a clinical prediction model for osteopenia in Chinese middle-aged and elderly men: a prospective cohort study

BACKGROUND

Early identification of patients at risk of osteopenia is an essential step in reducing the population at risk for fractures. We aimed to develop and validate a prediction model for osteopenia in Chinese middle-aged and elderly men that provides individualized risk estimates.

METHODS

In this prospective cohort study, 1109 patients who attend regular physical examinations in the Second Medical Centre of Chinese PLA General Hospital were enrolled from 2015.03 to 2015.09. The baseline risk factors included dietary habits, exercise habits, medical histories and medication records. Osteopenia during follow-up were collected from Electronic Health Records (EHRs) and telephone interviews. Internal validation was conducted using bootstrapping to correct the optimism. The independent sample T-test analysis, Mann_Whitney U test, Chi-Square Test and multivariable Cox regression analysis were utilized to identify predictive factors for osteopenia in Chinese middle-aged and elderly men. A nomogram based on the seven variables was built for clinical use. Concordance index (C-index), receiver operating characteristic curve (ROC), decision curve analysis (DCA) and calibration curve were used to evaluate the efficiency of the nomogram.

RESULTS

The risk factors included in the prediction model were bone mineral density at left femoral neck (LNBMD), hemoglobin (Hb), serum albumin (ALB), postprandial blood glucose (PBG), fatty liver disease (FLD), smoking and tea consumption. The C-index for the risk nomogram was 0.773 in the prediction model, which presented good refinement. The AUC of the risk nomogram at different time points ranged from 0.785 to 0.817, exhibiting good predictive ability and performance. In addition, the DCA showed that the nomogram had a good clinical application value. The nomogram calibration curve indicated that the prediction model was consistent.

CONCLUSIONS

Our study provides a novel nomogram and a web calculator that can effectively predict the 7-year incidence risk of osteopenia in Chinese middle-aged and elderly men. It is convenient for clinicians to prevent fragility fractures in the male population.

Association between serum cotinine and hepatic steatosis and liver fibrosis in adolescent: a population-based study in the United States

Tobacco exposure is known to be associated with a higher prevalence and incidence of liver diseases. Cotinine, a metabolite of nicotine, is a typical indicator of tobacco exposure. However, the relationship of serum cotinine levels with hepatic steatosis and liver fibrosis remains controversial and these relationships need more research to explored in American teenagers. Cross-sectional data included 1433 participants aged 12-19 from the National Health and Nutrition Examination Survey (NHANES) from 2017 to 2020 were thoroughly used for this study. The linear relationships between serum cotinine levels and the Liver Stiffness Measurement (LSM) and Controlled Attenuation Parameter (CAP) were examined using multiple linear regression models. Subgroup analysis, interaction tests, and nonlinear interactions were also carried out. Serum cotinine levels > 2.99 ng/ml [β = 0.41 (0.07, 0.76), p = 0.018] and 0.05-2.99 ng/ml [β = 0.24 (0.00, 0.49), p = 0.048] showed a significant positive connection with LSM in multivariate linear regression analysis when compared to serum cotinine levels ≤ 0.05 ng/ml (p for trend = 0.006). Moreover, we discovered an inverted U-shaped association of log2-transformed cotinine with LSM with an inflection point of 4.53 using a two-stage linear regression model. However, according to multiple regression analysis, serum cotinine and CAP did not significantly correlate (p = 0.512). In conclusion, this study demonstrated that smoking cessation and keep away from secondhand smoking may beneficial for liver health in American teenagers.

Association between secondhand smoke exposure and rheumatoid arthritis in US never-smoking adults: a cross-sectional study from NHANES

While smoking is widely acknowledged as a risk factor for rheumatoid arthritis (RA), the connection between secondhand smoke (SHS) exposure and RA in never-smoking adults remains limited and inconsistent. This study aims to explore and quantify this association using serum cotinine levels. We conducted a cross-sectional study with 14,940 adults who self-report as never smokers, using National Health and Nutrition Examination Survey data from 1999 to 2018. Based on previous literature, SHS exposure was categorized into four groups according to serum cotinine levels. Compared to individuals in the unexposed group (serum cotinine < 0.05 ng/mL), the adjusted odds ratio (OR) for RA was 1.37 (95% CI 1.14-1.64, p = 0.001) in the low exposure group (serum cotinine at 0.05 to 0.99 ng/mL) after adjusting for covariates. However, no significant association was found in the moderate exposure group (serum cotinine at 1 to 10 ng/mL) or the heavy exposure group (serum cotinine ≥ 10 ng/mL). Furthermore, we detected a non-linear, positively saturated correlation between the cotinine levels after log2 transformation and RA, with a turning point at approximately - 2.756 ng/mL (OR = 1.163, 95% CI 1.073-1.261, p = 0.0002). The stability of the results was confirmed by subgroup analysis.

Application of machine learning algorithms to identify people with low bone density

Background

Osteoporosis is becoming more common worldwide, imposing a substantial burden on individuals and society. The onset of osteoporosis is subtle, early detection is challenging, and population-wide screening is infeasible. Thus, there is a need to develop a method to identify those at high risk for osteoporosis.

Objective

This study aimed to develop a machine learning algorithm to effectively identify people with low bone density, using readily available demographic and blood biochemical data.

Methods

Using NHANES 2017-2020 data, participants over 50 years old with complete femoral neck BMD data were selected. This cohort was randomly divided into training (70%) and test (30%) sets. Lasso regression selected variables for inclusion in six machine learning models built on the training data: logistic regression (LR), support vector machine (SVM), gradient boosting machine (GBM), naive Bayes (NB), artificial neural network (ANN) and random forest (RF). NHANES data from the 2013-2014 cycle was used as an external validation set input into the models to verify their generalizability. Model discrimination was assessed via AUC, accuracy, sensitivity, specificity, precision and F1 score. Calibration curves evaluated goodness-of-fit. Decision curves determined clinical utility. The SHAP framework analyzed variable importance.

Results

A total of 3,545 participants were included in the internal validation set of this study, of whom 1870 had normal bone density and 1,675 had low bone density Lasso regression selected 19 variables. In the test set, AUC was 0.785 (LR), 0.780 (SVM), 0.775 (GBM), 0.729 (NB), 0.771 (ANN), and 0.768 (RF). The LR model has the best discrimination and a better calibration curve fit, the best clinical net benefit for the decision curve, and it also reflects good predictive power in the external validation dataset The top variables in the LR model were: age, BMI, gender, creatine phosphokinase, total cholesterol and alkaline phosphatase.

Conclusion

The machine learning model demonstrated effective classification of low BMD using blood biomarkers. This could aid clinical decision making for osteoporosis prevention and management.

The Association Between SHBG and Osteoporosis: A NHANES Cross-Sectional Study and A Bidirectional Mendelian Randomization

This study aimed to examine the association between sex hormone-binding globulin (SHBG) and osteoporosis through a cross-sectional study and a two-sample bidirectional Mendelian randomization (MR). We used the National Health and Nutrition Examination Survey (NHANES) 2013-2014 and 2015-2016 data, with exposure as serum SHBG and outcome as osteoporosis and performed multivariate logistic regression to test the correlation between SHBG and osteoporosis. To determine the causal relationship between SHBG and osteoporosis, a two-sample bidirectional MR was employed. The genome-wide association study (GWAS) dataset for SHBG (n = 189,473) was obtained from the IEU database, and the GWAS dataset for osteoporosis (n = 212,778) was obtained from the FinnGen bioBank. The principal MR technique was inverse-variance weighting (IVW). In MR analyses, the MR-Egger intercept and Cochran Q test were used to detect multiple validity and horizontal heterogeneity. 1249 older adult participants (age ≥ 60) were involved in the cross-sectional study, including 113 osteoporosis cases. We identified a significant relationship between circulating SHBG concentration and osteoporosis risk [OR 3.963, 95% CI (2.095-7.495), P < 0.05]. Subgroup analysis indicated that SHBG was closely linked to the risk of osteoporosis in the female population [OR 1.008, 95% CI (1.002-1.013), P = 0.005] but not in males (P = 0.065). In addition, The IVW approach suggested a causal connection between SHBG and increased osteoporosis risk [OR 1.479, 95% CI (1.144-1.912), P = 0.003], and the MR-Egger intercept and the Cochran Q test validated the consistency of the MR results. Finally, the reverse MR analysis declined to identify a causal relation between SHBG and osteoporosis. Our research demonstrates a significant causal connection between circulating SHBG levels and increased osteoporosis risk. These results indicate that high SHBG may be associated with the risk of osteoporosis in postmenopausal women, but more research is needed.

Smoking, alcohol consumption, drug abuse, and osteoporosis among older adults: a cross-sectional study on PERSIAN cohort study in Fasa

BACKGROUND

With increasing life expectancy and a growing population of older adults, the prevalence of osteoporosis has risen, resulting in a higher incidence of bone fractures, which necessitate extended treatment and specialized medical care. This study investigates the relationship between smoking, alcohol consumption, drug abuse, and osteoporosis among older adults in southern Iran, utilizing cohort data.

METHODS

This cross-sectional study is derived from the Fasa Adult Cohort Study (FACS), which included 10,133 individuals. From this cohort, we selected 1,631 older adults using census sampling methods. Our study aimed to explore the correlation between smoking, alcohol consumption, and drug abuse among older adults and the incidence of osteoporosis. We collected demographic information, nutritional indexes, medical history, glucocorticoid usage, and self-reported data on smoking, alcohol consumption, drug abuse, and osteoporosis through questionnaires. To investigate the relationship between smoking, alcohol, and drug use with osteoporosis while accounting for confounding factors, we employed logistic regression analysis.

RESULTS

The average age of the study participants was 64.09 ± 3.8 years, with a majority (898 (55.1%)) being female. Osteoporosis prevalence among the subjects was 25.20%. The results did not reveal a significant correlation between smoking, alcohol consumption, drug abuse, and osteoporosis (p > 0.05). Regression analysis identified gender, recent history of fractures within the past five years, history of using glucocorticoids, and physical activity as significant predictive risk factors for osteoporosis within the study population (p < 0.05).

CONCLUSION

The study underscores the significance of addressing osteoporosis risk factors in older adults. Healthcare policymakers and administrators can use these findings to identify and mitigate influential factors contributing to osteoporosis in this demographic.

Long-term exposure to PM1 is associated with increased prevalence of metabolic diseases: evidence from a nationwide study in 123 Chinese cities

Exposure to particulate matter (PM) has been linked to metabolic diseases. However, the effects of PM with an aerodynamic diameter ≤ 1.0 µm (PM1) on metabolic diseases remain unclear. This study is aimed at assessing the associations of PM1 with metabolic disease risk and quantifying the concentration-response (C-R) relationship of PM1 with metabolic disease risk. A national cross-sectional study was conducted, including 12,495 middle-aged and older adults in 123 Chinese cities. The two-year average concentration of PM1 was evaluated using satellite-based spatiotemporal models. Metabolic diseases, including abdominal obesity, diabetes, hypertension, dyslipidemia, and metabolic syndrome, were identified based on physical examination, blood standard biochemistry examination, and self-reported disease histories. Generalized linear models and C-R curves were used to evaluate the associations of PM1 with metabolic diseases. A total of 12,495 participants were included in this study, with a prevalence of 45.73% for abdominal obesity, 20.22% for diabetes, 42.46% for hypertension, 41.01% for dyslipidemia, and 33.78% for metabolic syndrome. The mean ± standard deviation age of participants was 58.79 ± 13.14 years. In addition to dyslipidemia, exposure to PM1 was associated with increased risks of abdominal obesity, diabetes, hypertension, and metabolic syndrome. Each 10 μg/m3 increase in PM1 concentrations was associated with 39% (odds ratio (OR) = 1.39, 95% confidence interval (CI) 1.33, 1.46) increase in abdominal obesity, 18% (OR = 1.18, 95%CI 1.12, 1.25) increase in diabetes, 11% (OR = 1.11, 95%CI 1.06, 1.16) increase in hypertension, and 25% (OR = 1.25, 95%CI 1.19, 1.31) in metabolic syndrome, respectively. C-R curves showed that the OR values of abdominal obesity, diabetes, hypertension, and metabolic syndrome were increased gradually with the increase of PM1 concentrations. Subgroup analysis indicated that exposure to PM1 was associated with increased metabolic disease risks among participants with different lifestyles and found that solid fuel users were more susceptible to PM1 than clean fuel users. This national cross-sectional study indicated that exposure to higher PM1 might increase abdominal obesity, diabetes, hypertension, and metabolic syndrome risk, and solid fuel use might accelerate the adverse effects of PM1 on metabolic syndrome risk. Further longitudinal cohort studies are warranted to establish a causal inference between PM1 exposure and metabolic disease risk.

Association of environmental tobacco smoke exposure with chronic constipation: a nationwide survey (NHANES 2005-2010)

Environmental tobacco smoke (ETS) exposure has been proven to induce digestive diseases such as hepatic steatosis, cirrhosis, and gastrointestinal cancer, yet little is known about the link between ETS exposure and constipation. This study aimed to investigate the impact of ETS exposure on the risk of chronic constipation in adults aged 20 years or older. This is a cross-sectional study based on population. A total number of 7705 participants from the National Health and Nutrition Examination Survey (NHANES) 2005-2010 were included. Cotinine, an alkaloid found in tobacco, serves as a reliable and precise biomarker for measuring exposure to ETS. Hence, the categorization of exposure to ETS was conducted based on serum cotinine levels, resulting in four distinct categories. The association between ETS exposure and the risk of constipation was assessed using multivariable restricted cubic spline and logistic regression with odds ratio (OR) and 95% confidence interval (CI). The weighted prevalence of constipation in this study was estimated to be 7.51% based on stool consistency, or 3.11% based on stool frequency. The fully adjusted models indicated a positive correlation between exposure to ETS and constipation as measured by stool frequency, among adults with poor dietary quality (OR (95% CI): moderate exposure: 2.49 (1.05, 5.94); high exposure: 2.36(1.13, 4.95), P for trend = 0.03), while no significant difference was observed in the subgroup with a higher healthy eating index. Furthermore, the log10-transformed serum cotinine level exhibited a non-linear inverted U-shaped association with constipation in individuals with poor dietary quality (P overall = 0.0207, P non-linear = 0.0427). Conversely, a J-shaped non-linear relationship was observed in the subgroup with a higher healthy eating index (P overall = 0.0028, P non-linear = 0.0036). Our results show that ETS exposure appears to be positively associated with stool frequency-related chronic constipation in adults with poor dietary quality.

Metal mixture and osteoporosis risk: Insights from plasma metabolite profiling

The pathophysiology of osteoporosis (OP) is influenced by exposure to nonessential harmful metals and insufficient or excessive intake of necessary metals. Investigating multiple plasma metals, metabolites, and OP risk among older adults may reveal novel clues of underlying mechanisms for metal toxicity on bone mass. A total of 294 adults ≥ 55 years from Wuhan communities were included. Plasma concentrations of 23 metals and metabolites were measured via inductively coupled plasma-mass spectrometry and global metabolite detection. To investigate the relationships between plasma metals, OP risk, and OP-related metabolites, three different statistical techniques were used: generalized linear regression model, two-way orthogonal partial least-squares analysis (O2PLS), and weighted quantile sum (WQS). The mean ages were 66.82 and 66.21 years in OP (n = 115) and non-OP (n = 179) groups, respectively. Of all 2999 metabolites detected, 111 differential between-group members were observed. The OP risk decreased by 58.5% (OR=0.415, 95% CI: 0.237, 0.727) per quartile increment in the WQS index indicative of metal mixture exposure. Consistency remained for bone mineral density (BMD) measurements. The O2PLS model identified the top five OP-related metabolites, namely, DG(18:2_22:6), 3-phenoxybenzoic acid, TG(16:1_16:1_22:6), TG(16:0_16:0_20:4), and TG(14:1_18:2_18:3), contributing most to the joint covariation between the metal mixture and metabolites. Significant correlations between each of them and the metal mixture were found using WQS regression. Furthermore, the five metabolites mediated the associations of the metal mixtures, BMD, and OP risk. Our findings shed additional light on the mediation functions of plasma metabolites in the connection between multiple metal co-exposure and OP pathogenesis and offer new insights into the probable mechanisms underpinning the bone effects of the metal mixture.

Advances in the interaction between endoplasmic reticulum stress and osteoporosis

The endoplasmic reticulum (ER) is the main site for protein synthesis, folding, and secretion, and accumulation of the unfolded/misfolded proteins in the ER may induce ER stress. ER stress is an important participant in various intracellular signaling pathways. Prolonged- or high-intensity ER stress may induce cell apoptosis. Osteoporosis, characterized by imbalanced bone remodeling, is a global disease caused by many factors, such as ER stress. ER stress stimulates osteoblast apoptosis, increases bone loss, and promotes osteoporosis development. Many factors, such as the drug's adverse effects, metabolic disorders, calcium ion imbalance, bad habits, and aging, have been reported to activate ER stress, resulting in the pathological development of osteoporosis. Increasing evidence shows that ER stress regulates osteogenic differentiation, osteoblast activity, and osteoclast formation and function. Various therapeutic agents have been developed to counteract ER stress and thereby suppress osteoporosis development. Thus, inhibition of ER stress has become a potential target for the therapeutic management of osteoporosis. However, the in-depth understanding of ER stress in the pathogenesis of osteoporosis still needs more effort.

Associations between smoke exposure and kidney stones: results from the NHANES (2007-2018) and Mendelian randomization analysis

Purpose

It is currently controversial whether smoke exposure is associated with the risk of kidney stones. Herein, publicly available databases were combined to explore relationships with the risk of nephrolithiasis in terms of smoking status and serum cotinine concentrations.

Materials and methods

First, we conducted an observational study using data from 2007 to 2018, based on the National Health and Nutrition Examination Survey (NHANES) database. Univariate analysis, multivariate logistic regression, trend testing, restricted cubic spline (RCS), and multiple imputation (MI) were the main analytical methods of our study. Then, A Mendelian randomization (MR) analysis was performed to explore the causal relationship between serum cotinine and nephrolithiasis. Genetic instruments for serum cotinine and pooled data for kidney stones were derived from publicly available large-scale genome-wide association studies (GWAS). Inverse-variance weighting (IVW) was the primary method for our MR analysis.

Results

A total of 34,657 and 31,352 participants were included in the observational study based on smoking status and serum cotinine concentrations, respectively. Under full adjustment of covariates, current smokers had an increased risk of kidney stones compared to non-smokers [OR = 1.17 (1.04-1.31), P = 0.009, P for trend = 0.010]. Compared with serum cotinine of <0.05 ng/ml, serum cotinine levels of 0.05-2.99 ng/ml [OR = 1.15 (1.03-1.29), P = 0.013] and ≥3.00 ng/ml [OR = 1.22 (1.10-1.37), P < 0.001] were observed to have a higher risk of nephrolithiasis (P for trend < 0.001). In addition, a non-linear relationship between log2-transformed serum cotinine and the risk of nephrolithiasis was found (P for non-linearity = 0.028). Similar results were found when serum cotinine (log2 transformation) was used as a continuous variable [OR = 1.02 (1.01-1.03), P < 0.001] or complete data was used to analyze after MI. In the MR analysis, genetically predicted high serum cotinine was causally related to the high risk of nephrolithiasis [IVW: OR = 1.09 (1.00-1.19), P = 0.044].

Conclusion

Current smoking and high serum cotinine concentrations may be associated with an increased risk of kidney stones. Further research is needed to validate this relationship and explore its underlying mechanisms.

Osteosarcopenia and Pain: Do We Have a Way Out?

Osteosarcopenia (OSP) is a geriatric syndrome characterized by the coexistence of osteoporosis and sarcopenia and associated with an increased risk of fragility fractures, disability, and mortality. For patients with this syndrome, musculoskeletal pain represents the most significant challenge since, in addition to limiting the individual's functionality and promoting disability, it has a huge psychological burden involving anxiety, depression, and social withdrawal. Unfortunately, the molecular mechanisms involved in the development and persistence of pain in OSP have not yet been fully elucidated, although immune cells are known to play a key role in these processes. Indeed, they release several molecules that promote persistent inflammation and nociceptive stimulation, resulting in the gating of ion channels responsible for the generation and propagation of the noxious stimulus. The adoption of countermeasures to counteract the OSP progression and reduce the algic component appears to be necessary, providing patients with a better quality of life and greater adherence to treatment. In addition, the development of multimodal therapies, based on an interdisciplinary approach, appears to be crucial, combining the use of anti-osteoporotic drugs with an educational programme, regular physical activity, and proper nutrition to eliminate risk factors. Based on this evidence, we conducted a narrative review using the PubMed and Google Scholar search engines to summarize the current knowledge on the molecular mechanisms involved in the pain development in OSP and the potential countermeasures to be taken. The lack of studies addressing this topic highlights the need to conduct new research into the resolution of an ever-expanding social problem.